Modified Stroop Task Research Articles

Mood-congruent free recall bias in anxious individuals is not a consequence of response bias

The status of mood-congruent free recall bias in anxious individuals was evaluated following incidental encoding of target words. Individuals with high and low levels of trait anxiety completed a modified Stroop task, which revealed an attentional bias for threat-related stimuli in anxious individuals. This group was significantly slower in naming the colour in which threat-related words were displayed compared to neutral words. In a subsequent free recall test for the words used in the modified Stroop task, anxious individuals recalled more threat-related words compared to low-anxious people. This difference was significant even when controlling for the false recall of items that had not been presented during study. These results support the view put forward by Russo, Fox, Bellinger, and Nguyen-Van-Tam (2001) that mood-congruent free recall bias in anxious individuals can be observed if the target material is encoded at a relatively shallow level. Moreover, contrary to Dowens and Calvo (2003), the current results show that the memory advantage for threat-related information in anxious individuals is not a consequence of response bias.

Nicotine Stroop and addiction memory—an ERP study

Drug-related cues have been shown to take effects on behavioral performance and physiological parameters such as event-related brain potentials (ERPs). In the present study we obtained EEG data during a modified Stroop task and during a color matching task using smoking related and neutral words (nicotine Stroop) in smokers and non-smoking controls. We assumed that in smokers smoking-related word meanings would interfere with color matching, and that this should be reflected in an ERP activation pattern comparable to that induced by the Stroop task. In smokers and non-smokers the classic Stroop-related interference effect of longer reaction times in the incongruent condition could be observed. This interference effect in both groups was related to a late posterio-central relative negativity and a right frontal relative positivity in the incongruent compared to the congruent condition. The behavioral data in the color matching task (nicotine Stroop) derived from both groups did not show a comparable interference effect related to the use of drug-related words. However, in smokers the smoking-related words elicited ERP activation patterns comparable to those evoked by the Stroop interference task. The ERP results are discussed as possibly reflecting a modulation of color processing of smoking-related words in smokers. The results imply an interference, but also attention enhancing, effect of smoking-related words in smokers, which maybe associated with addiction memory and enhanced sensitivity for drug-cues. Therefore, the addiction memory driven interference effect might be counteracted by performance enhancement induced by the same nicotine cues.

Victim’s innocence, social categorization, and the threat to the belief in a just world

This research studies people’s reactions to the suffering of victims, examining the hypothesis of the belief in a just world (BJW) ( Lerner, 1980) according to which the awareness of innocent victims threatens people’s BJW, and extending the scope of BJW theory to intergroup contexts. An implicit measure of the threat to the BJW ( Hafer, 2000a) is used in this research. After participants viewed a videotaped film containing the victimization story they performed an emotional modified Stroop task. Study 1 examined the threat to the BJW as function of the innocence of the victim at an interpersonal level of analysis. Results show that only the innocent victim threatens the observer’s BJW. Study 2 examined the threat to the BJW as function of the victim’s group and of the victim’s innocence. Results show that an ingroup victim threatens the participant’s BJW more than a victim belonging to an outgroup.

Association of serotonin transporter genotype with selective processing of smoking‐related stimuli in current smokers and ex‐smokers

We sought to determine whether polymorphism in the serotonin transporter (5HTT) gene is associated with attentional bias toward smoking-related stimuli in current smokers and ex-smokers, using a modified Stroop task and an attentional blink task to measure selective processing of smoking-related stimuli. All participants attended a single testing session during which they completed the modified Stroop and attentional blink tasks to index attentional bias for smoking-related stimuli, in counterbalanced order. The experimental design included two between-subjects factors of smoking status (current smoker, ex-smoker) and 5HTT genotype (short, long). Smoking status x genotype interactions were significant on both the modified Stroop (p = .046) and the attentional blink (p = .006) tasks. On the modified Stroop task, we found a significant effect of 5HTT genotype on color-naming interference among ex-smokers (p = .018) but not current smokers (p = .989). On the attentional blink task, we found a significant effect of 5HTT genotype for current smokers (p = .028), whereas among ex-smokers this effect did not reach statistical significance, although it constituted a trend (p = .086). Our data provide tentative support for a moderating influence of 5HTT genotype on attentional bias for smoking-related stimuli in ex-smokers. This finding may account for inconsistent reports of attentional bias among ex-smokers.

Cannabis ???dependence??? and attentional bias for cannabis-related words

Drug users have attentional biases for drug-related stimuli, and the frequency of drug use and craving are associated with attentional bias. However, research to date has not investigated the relationship between the severity of cannabis dependence, and attentional bias for cannabis-related stimuli. In the present study, 28 recreational cannabis users completed a modified Stroop task with cannabis-related and control words, plus questionnaire measures of cannabis dependence and craving. Participants were split into those who met diagnostic criteria for cannabis dependence based on scores on the Cannabis Severity of Dependence Scale (C-SDS), and those who did not. The cannabis-dependent group had a significant attentional bias for the cannabis-related words, but the non-dependent group did not. Correlations indicated that attentional bias was also associated with the frequency of cannabis use, and with subjective craving.

Hypervigilance and Attentional Fixedness in Chronic Musculoskeletal Pain: Consistency of Findings Across Modified Stroop and Dot-probe Tasks

Results from modified Stroop and dot-probe tasks have provided mixed evidence regarding attentional biases for sensory and affect pain stimuli in chronic pain patients. No studies have compared the same groups of chronic pain and healthy control participants on both tasks. We tested 36 patients with chronic musculoskeletal pain and 29 healthy control subjects on the modified Stroop and dot-probe tasks. Stimuli comprised affect pain, sensory pain, physical catastrophe, and neutral words. There was no evidence to suggest differential processing of threat cues by patients and control subjects on the modified Stroop task. All participants did, however, show differential processing of affect pain words. This was evident on both masked and unmasked presentation formats. There were no significant interactions between clinical status and threat word type observed for any of the indices of selective attention derived from the dot-probe task, but all participants had difficulty disengaging attention from affective pain and health catastrophe words. Findings were not influenced by individual differences in mood, anxiety, or fear of pain. Correlational analyses of the standard (unmasked) Stroop interference index and dot-probe indices of selective attention revealed a consistent lack of significant association, suggesting that the 2 tasks might be measuring different phenomena. Taken together, these findings provide evidence that chronic pain patients and healthy control participants do not differ in the way they attend to threatening linguistic stimuli. Perspective Some patients with chronic pain might have trouble paying attention to anything other than the affective components of pain and associated catastrophic health consequences. Interventions that specifically target this attentional fixedness might facilitate shifting attention to other targets and thereby reduce pain-specific anxiety and fear.

An Examination of Word Relevance in a Modified Stroop Task in Patients with Chronic Low Back Pain

The present study examined the role of personal relevance of sensory pain-related words in selective attentional processing measured with a modified Stroop task administered to 30 patients with chronic low back pain. A related aim of this study was to introduce the application of multilevel analysis to test the influence of personal relevance on selective attentional processing in this sample. Patients completed the modified Stroop task, as well as a set of self-report measures aimed to assess Fear of Pain, Trait Anxiety, Catastrophizing, Pain Vigilance, and Pain Intensity. The modified Stroop task comprised 33 sensory pain-related words for which the personal relevance towards current concerns was rated afterwards by each participant on a 7-point Likert-type scale. The multilevel analyses did not support the hypothesis that personal relevance of sensory pain-related words interacted with Fear of Pain scores of patients in accounting for reaction times in naming the color of sensory pain-related words. None of the other self-report measures accounted for reaction times in isolation or in interaction with personal relevance. The modified Stroop task does not appear to be a robust measure of selective attentional processing in patients with chronic low back pain. The usefulness of other paradigms, such as the visual dot-probe task, should be explored in examining selective attentional processing in this population.

Adjustments of Cognitive Control in Younger and Older Adults

The effects of aging on behavioral and electrophysiological indices of adjustments of cognitive control were examined in two experiments. Specifically, we considered the effects of aging of patterns of response time and modulations of the event-related brain potentials (ERPs) on sequential trial effects, error-related slowing, and local switch costs in two modified Stroop tasks. The behavioral data reveal that sequential trial effects were observed when color, but not word, identification was required and that these effects were similar in younger and older adults; that the degree of error-related slowing was similar for younger and older adults in Experiment 1 and greater in older than younger adults in Experiment 2; that local switch costs in response time were similar in younger and older adults and that the requirement to switch between color and word identification resulted in a dramatic increase in the number of color intrusion errors in older adults in Experiment 2. The ERP data revealed that endogenously generated adjustments of cognitive control were associated with a parietal slow wave that mirrored the behavioral data and was similar in amplitude in younger and older adults and an anterior frontal slow wave that was absent in older adults. The ERP data also revealed that an enhancement of the P3 component and a frontal slow wave that differentiated color switch trials from color non-switch and word trials in younger adults were attenuated in older adults.

Is Beautiful Always Good? Implicit Benefits of Facial Attractiveness

A theme that emerges in life is that it is advantageous to be good looking. Corroborating this observation, an expansive literature has documented the benefits of facial attractiveness on a range of explicit measures. What is not yet known, however, is whether this association between beauty and positivity also exerts an implicit influence on people's responses. That is, does the “beautiful is good” stereotype operate when attention is not explicitly directed to a person's appearance? Using a modified Stroop task, we explored this issue in the current investigation. The results revealed that facial stereotypes do indeed exert an automatic influence on people's responses, an effect that is elicited by targets of either sex and displayed by both male and female respondents. In addition, female faces elicited positive evaluative responses (i.e., female–positivity effect). We consider the implications of these findings for issues in person perception.

Changes in cerebral hemodynamics during a cognitive task after caffeine ingestion

The present study was carried out to clarify whether caffeine affects cerebral hemodynamics in the prefrontal cortex association area in young male subjects during a cognitive task. Relative changes in blood volume and oxygenation in the prefrontal association cortex were measured noninvasively using continuous-wave near-infrared spectroscopy. A modified Stroop color-word task we developed was employed as a cognitive task to activate the prefrontal association cortex. The results showed that caffeine ingestion affects cerebral hemodynamics during the modified Stroop task, and suggested that the decrease in oxygenated hemoglobin may be related to deterioration of performance on the cognitive task following caffeine ingestion.

Information processing biases in eating disorders

Research has supported a link between emotional disorders (such as depression and anxiety) and information processing biases of attention and memory. This article reviews the extension of this approach to such biases in eating disorders. Two paradigms are considered in detail: the modified Stroop task and the dot probe task. In addition, the relative merits and problems associated with both approaches are considered. The limitations of the current research for clinical practice are discussed and suggestions are made for ways in which the research may be made more ecologically valid.

Cognitive and Psychophysiological Correlates of Subsyndromal Seasonal Affective Disorder

This study longitudinally examined cognitive and psychophysiological factors in females who met criteria for subsyndromal seasonal affective disorder (S-SAD) and nondepressed, low seasonality controls. Participants (N = 46) were tested twice, during one winter month (i.e., December or January) and during one nonwinter month (i.e., September or April). At each assessment, participants completed measures of negative automatic thought frequency, mood, and seasonality as well as three experimental tasks (a psychophysiological task, a schematic faces task, and a modified Stroop task). Women with S-SAD and controls differed at both assessments on frequency of automatic negative thoughts and emotional and psychophysiological reactivity to light-relevant stimuli. These results highlight the need for research examining a possible cognitive vulnerability to symptom development and maintenance across the spectrum of seasonality.

Attentional Bias and Drinking to Cope With Social Anxiety.

This study investigated the sensitivity of the emotional Stroop test for identifying individuals who reported drinking to cope with social fears. Community volunteers completed a modified Stroop task during which social threat, alcohol-related, and control words were presented. High scores on drinking-to-cope measures were hypothesized to be associated with longer response latencies to both social threat and alcohol-related words. Consistent with previous studies, alcohol dependence was correlated with latencies for alcohol-related words, and level of social anxiety was correlated with response latency to social threat words. As expected, drinking-to-cope measures predicted response latency to alcohol-related and social threat words. These results suggest that the emotional Stroop test is useful in studying the relationship between social anxiety and alcohol consumption.

Clinical utility of the modified Stroop task as a treatment outcome measure: Questions raised

Data from an outpatient treatment trial for anorexia nervosa were examined to gain preliminary insights as to whether the modified Stroop colour-naming task might offer a useful measure of treatment outcome. It was hypothesised that interference for eating-, weight- and shape-related words on a modified version on the Stroop colour-naming task would decrease with successful treatment. Studies to date suggest that eating disorder patients show interference on the Stroop colour-naming task for food- and shape-related words. The study was designed to assess selective-information changes for patients with anorexia nervosa before and after treatment in association with other psychological measures. Pretreatment and post-treatment assessments were collected from a clinical trial of 25 women who met Diagnostic and Statistical Manual of Mental Disorders (4th ed., DSM-IV) criteria for anorexia nervosa. Using repeated measures analysis of variance, a significant Time × Card interaction was found on the Food and Control Food Stroop cards, indicating that interference decreased following treatment. The results of this preliminary study raise numerous questions for further research. These findings suggest that the modified Stroop colour-naming task may be sensitive to change among anorexia nervosa patients and may potentially provide a valuable measure of treatment outcome. Comparison with a nonclinical group needs to be made to determine whether the reduction in Stroop scores is a normative process. Furthermore, studies with larger sample sizes are needed to compare treatment responders and nonresponders with matched controls to rule out the possible influence of a practice effect.

Effects of Thought Suppression on Subliminally and Supraliminally Presented Food-related Stimuli

AbstractThis study investigates whether hyperaccessibility occurs for supraliminally or subliminally presented sweets-related stimuli after prior suppression of thoughts about sweets. Thirty-three students (all female; 18—25 years old) participated in the experiment. In the first phase, half of the experimental group was instructed to suppress all sweets-related thoughts. The other participants were given control instructions. In the second phase, as part of a modified Stroop task, participants were asked to state the colour of a stimulus as quickly as possible. This stimulus could be presented either subliminally or supraliminally. In both conditions, neutral control words as well as sweets words were used. It was found that the participants in the suppression group, compared to those in the control group, showed attentional bias for the sweet-related suppressed thoughts, but that this effect was determined by the reaction times of subliminally presented sweets words. No differences were found for the control words. In addition, the study explored whether there was a relationship between thought suppression and dietary restraint attitudes. The link to dietary behaviour, however, remains unclear.

Individual Cerebral Hemodynamic Response to Caffeine Was Related to Performance on a Newly Developed Stroop Color-Word Task

A modified Stroop color-word task has been developed to activate the prefrontal cortex as a cognitive task and it has been tried to clarify whether change in the cerebral hemodynamics after ingesting caffeine is associated with change in performance on the modified Stroop task in young male subjects. In this modified task, subjects were instructed to quickly select a colored disk on a computer screen in response to an instruction, i.e. “color” or “meaning”, presented simultaneously with one color word at each trial. The color of the presented color word was discordant with the meaning of the word. Relative changes in blood volume and oxygenation in the prefrontal association cortex were measured noninvasively using continuous-wave near-infrared spectroscopy. The results showed that caffeine ingestion decreased blood volume and oxygenated hemoglobin concentration in the brain during the modified Stroop task, and that the individual change in the latter was related to change in performance on the task following caffeine ingestion.

Selective processing of negative emotional information in children and adolescents with Generalized Anxiety Disorder.

Research investigating attentional bias for emotional information using the modified Stroop task in younger anxious populations has produced equivocal results. The present data investigated the replicability in younger participants of the prototypical adult finding of Mathews and MacLeod (1985) with patients with Generalized Anxiety Disorder (GAD). A sample of 19 child and adolescent patients with GAD and 19 controls completed the modified Stroop paradigm with threat, depression-related, positive and neutral words. The data revealed a selective Stroop interference effect for negative emotional information in the GAD patients, relative to the performance of the controls. The results provide evidence of a modified Stroop effect for negative emotional material in children and adolescents with GAD, suggesting that modified Stroop processing in younger generally anxious populations broadly mirrors the profile of results in adults.

Experimental evidence for interpretive but not attention biases towards somatic information in patients with chronic fatigue syndrome.

This study tested whether CFS patients have an attentional information processing bias for illness-related information and a tendency to interpret ambiguous information in a somatic fashion. 25 patients meeting research criteria for a diagnosis of CFS were compared to 24 healthy matched controls on a modified Stroop task and an ambiguous cues task. In the modified Stroop task, participants colour named a series of somatic, depressed and neutral words in order to ascertain whether the somatic words were more distracting to the CFS patients than the depressed and neutral words when compared to controls. In the ambiguous cues task, participants were presented with a tape-recorded list of 30 words including 15 ambiguous illness words (e.g., vein/vain) and 15 unambiguous words. For each word, they were asked to write down the first word that came into their head. A somatic bias score was obtained for each subject by summing the number of somatic responses to the ambiguous word cues. Although CFS patients were significantly slower in colour naming all of the Stroop word categories than controls, there was no evidence for illness or depressed words creating greater interference than neutral words. However, on the ambiguous cues task, CFS patients made significantly more somatic interpretations than controls and this bias was significantly associated with the extent to which they currently reported symptoms. CFS patients have an interpretive bias for somatic information which may play a part in the maintenance of the disorder by heightening patients' experience of physical symptoms and helping to maintain their negative illness schemas. Although patients did not show an attentional bias in this study, this may be related to the methodology employed.

Brain activation patterns during a selective attention test—a functional MRI study in healthy volunteers and patients with schizophrenia

Functional magnetic resonance imaging was used to compare cortical activation patterns in healthy volunteers with those in patients with schizophrenia during a modified verbal Stroop task. Healthy subjects ( n=13) and patients with schizophrenia ( n=13) on stable antipsychotic treatment, matched on demographic variables, were included. Patients were preselected on the basis of good performance on a selective attention test. Patients with schizophrenia showed a significantly increased pattern of activation in the left and right inferior frontal cortex and the anterior cingulate cortex. A significant negative correlation between activation of the left prefrontal cortex and accuracy in the modified Stroop test was observed for healthy controls but not schizophrenia patients. Although both groups recruited the prefrontal cortex during the modified Stroop task, for the schizophrenia patients this activation was bilateral, whereas for the controls this activation was primarily in the left hemisphere, suggesting that patients with schizophrenia recruited more prefrontal regions to perform the task with the same accuracy as healthy controls. Our findings of increased activity across multiple areas of the brain, including dorsolateral frontal cortex and anterior cingulate, in patients with schizophrenia who perform relatively well on a task of selective attention give further evidence that task performance may be a confounding factor in the interpretation of neuroimaging results.

The Guilty Knowledge Test and the modified Stroop task in detection of deception: an exploratory study.

The current study tested whether a simple Stroop paradigm can be used to detect deceptive behavior. 40 university students (34 women), half of whom committed a mock crime, were administered a Guilty Knowledge Test and modified Stroop task to detect guilt or innocence. The Guilty Knowledge Test is a well-known psychophysiological detection method, which consists of multiple-choice questions about details of the crime while skin conductance is recorded. Subjects possessing guilty knowledge are expected to show enhanced differential responses to the relevant stimuli. The modified Stroop task required color-naming of colored words related to the mock crime or an irrelevant crime. Each version of the Stroop task was presented in story form. Subjects possessing guilty knowledge were expected to produce larger reaction times to the relevant version relative to the irrelevant version. The test correctly identified 100% of innocent participants and 78% of guilty participants. In contrast, Stroop interference. i.e., reaction times for irrelevant crime details subtracted from those for mock crime details, did not differentiate between the two groups, suggesting that the story form of the Stroop paradigm is not suitable for lie detection.